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Background: The 8th version of the "World Checklist of Vascular Plants" (WCVP) was recently published under the coordination of the Royal Botanic Gardens, Kew. It consists of a list of taxonomic names of species, genera, and families of vascular plants representing the most comprehensive and integrated list available today. Questions: How many accepted species does the WCVP include? Is the quality of the included information acceptable? How has the publication of worldwide species names evolved over time? Does the checklist include the species recorded for Mexico? Studied species: Worldwide species of vascular plants included in the WCVP. Study site: Worldwide and Mexico. Methods: A database was created based on the WCVP to answer the research questions. The number of genera and species by taxonomic status (accepted and synonyms) was quantified, some information quality tests were carried out, and the potential number of undiscovered species in the world was estimated using non-parametric techniques. Results: The WCVP contains 1,233,172 names, of which 418,737 are accepted. It is estimated that around 25 % more unknown species remain to be discovered in the world. The quality of the information contained in the WCVP is quite reliable and complete; only 3 % of Mexican species are not included in the WCVP. Conclusions: The WCVP synthesizes current taxonomic knowledge in an integrated manner and is useful for systematic and automated analyses. At the country level, at least for Mexico, it stands as an important reference source when attempting to understand and evaluate floristic knowledge.

Con base en ejemplares de herbario recolectados, identificados y georreferenciados provenientes del territorio considerado por el proyecto Flora del Bajío y de regiones adyacentes, se analiza la riqueza de Asteraceae conocida en dicha región. Utilizando una división de la región en cuadros de 0.5° x 0.5°, el objetivo fue identificar los sitios de alta diversidad para la familia. La región tiene documentadas, con los ejemplares de herbario revisados, 681 especies de Asteraceae, distribuidas en 182 géneros; aquellos con mayor número de especies sonAgeratina (39), Stevia (31), Verbesina (29) y Acourtia (27), mientras que 82 registran una sola. En promedio se encontró una proporción de 3.7 especies por género. Querétaro es la entidad federativa que más especies registró (504), seguida de Michoacán (490) y Guanajuato (389). Análisis estadísticos proyectan la existencia de 773 especies para la región de estudio, de las cuales se han registrado 681 (88% de las especies esperadas; de ese porcentaje faltante, al menos 66 (67%) han sido reportadas de alguna parte del Bajío y regiones adyacentes, pero hasta la fecha no se han observado ejemplares de herbario que respalden su presencia. Se evalúa la riqueza por cuadro y se proponen algunos considerados importantes para llevar a cabo futuras estrategias de conservación con base en los patrones de riqueza encontrados.

Background: The first monograph of the genus Viguiera was published in 1918 by Blake, including about 141 species. Schilling & Panero based on studies of molecular sequences of nuclear Internal Transcribed Spacer and External Transcribed Spacer, as well as cpDNA, proposed to reclassify the genus, relocating its species in at least other nine genera. Question: Is it possible to identify distinctive patterns between the species of the new classification of Viguiera s. l. and the results of the chemical studies reported? Species considered: Sixty-seven species within the wide Viguiera circumscription with chemical studies and biological activities reported. Results: The species of the genus Viguiera synthesize terpenoids represented mainly by sesquiterpene lactones and diterpenes, with triterpenes, polyacetylenes, volatile terpenoids and flavonoids also present. The main types of secondary metabolites were present in the studied species, although some compounds were more frequent than others in some clades. Conclusion: Germacrolides, heliangolides, furanoheliangolides, tetracyclic diterpenes and flavonoids are the main constituents of Viguiera and segregated genera. Some interesting chemotaxonomic relationships are noted. Nevertheless, nondistinctive clear patterns were observed between clades and chemical groups. These results may be a consequence of the reported chemical studies of the species of Viguiera s. l., which have not agreed on objetives or methodologies.

Mexico has over 23,300 vascular plant species, half of which are endemic, and ranks third in species richness in the Americas. Compiling checklists and floras, and examining phylogenetic relationships are the ways we develop a better understanding of species richness. The plant checklist and the metadata of the sequences in GenBank can help determine how well represented Mexico’s vascular flora is, using the taxonomic and systematic studies done in Mexico and internationally. We formulated eight questions related to biological aspects, bibliometric indicators, methods, and the markers used in phylogenetic studies for species distributed in Mexico. The list of Mexico’s vascular species published in taxonomy and systematics articles was used to extract GenBank’s metadata using Datataxa. The selection, filtering, and descriptive statistics were obtained with scripts designed for this study. We found that 12,589 species have sequence records in GenBank, published in 3,807 articles. The journal Systematic Botany has more than 400 publications. The number of authors ranges from 1 to 6. Average impact factor was 1.64. Magnoliophyta, Poales, and Poaceae have the highest number of published articles. Parsimony and ITS are the most widely used method and marker, respectively. We explore the importance of Mexico as a biological repository for understanding the evolution of plants in global science. This is the first study on the importance of a country’s flora in phylogenetic work. Numerous groups and endemic species lack sequencing data that could contribute to the resolution of different lineages in the phylogeny.

Advancing our current knowledge on floristic richness in Mexico requires access to different sources, including published and unpublished inventories, fascicles of ongoing floristic projects, and publicly available online databases. The evaluation of these sources reveals how extensive the information available on the country’s floristic diversity is, its heterogeneity, and the lack of protocols and standards for its proper organization, analysis, and synthesis. This review addresses the extent to which these sources of information provide the basis to achieve the long-awaited goal of completing the Flora of Mexico, and how traditional outputs of taxonomic work (Floras and checklists) are useful to other fields of biological research. We identified major knowledge gaps, as well as actual and potential uses by other scholars and the public. Although all reviewed sources focus on a better knowledge of the Mexican plant species, each one has its own approach, geographic coverage, and objectives, producing incompatibilities that hamper their integration for rapid and efficient synthesis and analysis. Such integration should offer an updated scenario of its taxonomic and geographical coverage, setting the foundations for organized protocols and strategies aimed to complete the Flora of Mexico in the short term. Floristic knowledge for the country continues to advance actively, as indicated by the growing number of floristic inventories and the buildup of online databases. This synthesis shows how much we know today about Mexico’s vascular plant richness and highlights the relevance of this knowledge to other fields of study of nature, particularly those related to its plant component.

Background: Different regionalizations have been proposed for the Sierra Madre Oriental (SMOR), but none of them have analyzed its full floristic diversity. Hypothesis: The geographical distribution of the vascular plant species of the SMOR allows the identification of floristic regions with unique species that identify them as biogeographic units. Studied species: Vascular plants. Study site: Sierra Madre Oriental physiographic province, Mexico. Methods: Plant species distribution was analyzed in 1 × 1° latitude and longitude grid cells. Characteristic species (those with half or more of their known geographical distribution in Mexico in the SMOR) were identified, and a classification method was applied to distinguish biogeographic regions. Results: 8,472 species were recorded in the Sierra Madre Oriental, 3,433 of them considered characteristics, of which 2,158 are endemic to Mexico and 585 are considered strictly endemic to the province. The portions of the SMOR in the states of Coahuila, Nuevo León, Tamaulipas, and San Luis Potosí have a higher species richness and this richness decreases towards the south of the province. Five floristic districts were identified within the SMOR. Conclusions: The phytogeographic analysis carried out and its comparison with other regionalizations shows there is still disagreement in the biogeographic delimitation of the Sierra Madre Oriental and to achieve this goal it is necessary to include neighboring provinces in the analyzes, which will allow to identify their unique species and define their biogeographic limits in a more precise way.

— The genus Spigelia (Loganiaceae) is a Neotropical genus that includes more than 80 species distributed from the United States to Argentina. Systematic studies of the group have rarely considered the carpological characters, so their taxonomic importance has not been analyzed in detail. The aim of this study is to analyze the morphological characteristics of these organs to provide more information for a better species separation and for a more robust infra-generic classification. We provide a detailed description of Spigelia fruits and seeds of the Mexican species since the country represents one of its main centers of diversification. Fruits and seed samples from 54 individuals across 14 species were measured and photographed to describe each one, maintaining as much detail as possible. With the morphological matrix a DFA, PCA, and a dendrogram using the NJ method was performed. The fruits and seeds of the Mexican Spigelia species proved to be taxonomically useful, allowing the differentiation of four main clusters of species separated by the size of the analyzed structures in the three analyses (DFA, PCA, NJ). The results show the variation in size and shape of the structures analyzed, which shows the taxonomic importance of fruits and seeds of the genus Spigelia. Our work represents an advance in the detailed knowledge of structures, which are rarely considered in the descriptions, and which allows us to have a separation of species. A taxonomic treatment and photographs of the fruits and seeds are also included.

Calea ternifolia Kunth (Asteraceae), the “dream herb”, is an important medicinal plant that grows from Mexico to Costa Rica. The plant is highly valued for rituals and for treating several illnesses including anorexia, upset stomach, diabetes, periodic fevers, diarrhea, bile problems, and skin diseases. This comprehensive literature survey on C. ternifolia was performed up to January 2021. Our review focuses on traditional uses, botanical aspects, chemical constituents, quality control tests, as well as pharmacological and toxicological studies. Data were recorded using online scientific databases including Scopus, PubMed, Google Scholar, Taylor and Francis Imprints, National Center for Biotechnology Information, Science Direct, JSTOR, and SciFinder. The information was assembled from research articles, relevant books on herbal medicinal plants and the history of medicinal plants from Mexico, theses, reports, and web pages. The more significant botanical and ethnomedical aspects were recorded including the discovery of the oneirogenic use (enhancer of dreams) of C. ternifolia by the Chontal Indigenous communities in Oaxaca, Mexico. The plant contains sesquiterpenes and flavonoids as the major constituents. Some properties associated with the plant’s traditional uses have been demonstrated including spasmolytic, antidiabetic, antidepressant, anti-inflammatory, and antinociceptive effects. The plant’s toxicity will be discussed in this paper. Solid pharmacological research provided evidence supporting the use of the dream herb for oneiromancy.

Antecedentes y Objetivos: En los estudios sistemáticos el uso de los caracteres anatómicos es de gran relevancia para apoyar o refutar la circunscripción de géneros y especies. Nahuatlea es un género de la tribu Gochnatieae (Asteraceae), que incluye seis especies sustentadas con evidencia molecular. Sin embargo, sus caracteres anatómicos aún no han sido evaluados desde el punto de vista taxonómico. El objetivo de este trabajo fue describir la arquitectura y anatomía foliar, así como la anatomía de la madera de las especies de Nahuatlea y sus grupos hermanos Tehuasca, Anastraphia y Cnicothamnus para evaluar e identificar atributos con posible valor sistemático. Métodos: Se analizaron muestras de madera y hojas de tres individuos por especie, mediante técnicas convencionales de microtecnia para obtener y describir los caracteres cualitativos y cuantitativos. Estos se analizaron mediante modelos mixtos lineares generalizados y análisis de agrupación aglomerativa. Resultados clave: Caracteres de la madera como porosidad, disposición de los vasos, apertura de las punteaduras intervasculares y número de series en los radios presentan posible valor taxonómico. Por ejemplo, vasos con un patrón diagonal son exclusivos de N. hypoleuca, mientras que los radios bi o triseriados lo son para todas las especies de Nahuatlea. En la hoja, los patrones de venación y la presencia de extensiones de vaina e hipodermis presentan posible valor taxonómico. Las vénulas ramificadas e hipodermis de un estrato son exclusivos de N. purpusii. Los análisis mostraron diferencias significativas para algunos caracteres de la madera y la hoja. Conclusiones: La anatomía de madera y hoja permite reconocer combinaciones únicas de caracteres que apoyan la delimitación de las especies de Nahuatlea.

Antecedentes y Objetivos: Las Asteraceae ocupan un lugar predominante en la flora de México y en muchas otras partes del mundo. El recuento de su número de especies, géneros y tribus a escala nacional puede considerarse confiable, pero a escala más local su conocimiento aún es deficiente, pues existen todavía muchas áreas sin exploración. Este trabajo se planteó el objetivo de identificar la diversidad de especies de Asteraceae en el municipio Tepoztlán, Morelos, México, así como de analizar su distribución en los principales biomas registrados en el municipio y documentar su estado de conservación. Métodos: Para documentar la diversidad florística del municipio, se revisó literatura exhaustivamente, material herborizado recolectado en el municipio y depositado en diferentes colecciones (23 herbarios, especialmente JES, MEXU, SLPM y XAL), y se llevó a cabo trabajo de campo para recolectar material de la familia en diferentes localidades del municipio. Resultados clave: En el municipio Tepoztlán, Morelos, se registran 256 especies, distribuidas en 98 géneros y 19 tribus; 121 especies (47.3% del total) son endémicas de México y cuatro introducidas (exóticas). Más de 170 botánicos han realizado el esfuerzo de recolecta en el municipio, pero destacan nueve de ellos por su mayor número de recolectas. Por su número de especies destacan las tribus Eupatorieae (55) y Heliantheae (54), y a nivel de géneros sobresalen Heliantheae (24), Millerieae (15) y Eupatorieae (11). Los géneros Ageratina y Stevia registran el mayor número de especies (20 y 17 respectivamente). Los bosques templados del municipio registran un mayor esfuerzo de recolecta, seguidos por el bosque tropical estacionalmente seco; los fragmentos de bosque húmedo de montaña son los menos explorados. Conclusiones: Aunque el municipio es tal vez el mejor conocido en cuanto a su diversidad de Asteraceae, se subraya la necesidad de continuar con los trabajos de inventario florístico.

To study synanthropic plants (weeds), weeds need to be separated from non-weeds, a difficult task due to the existing gradient in nature. A representative family of the Mexican flora (Asteraceae) and a state very rich in species (Michoacán) are used as a model for this task and additional analyses. A total of 357 weeds are listed based on a critical review of specimens and bibliographic information, as well as defined criteria. In addition, tribes, growth forms, and geographic similarities with other states are examined for endemic, more widespread native, and introduced weeds. The main difficulty in differentiating weeds from non-weeds was the lack of accurate habitat information on herbarium labels. Most species grew in both disturbed and natural environments. Nearly half were endemic to the country, with only 4% introduced. The major Asteraceae tribes had relatively similar proportions of weeds, but exotics were concentrated in the tribe Cichorieae. Floristic similarities were mainly towards south-central Mexico. Most species were herbs and less than half annuals. We contribute to the delimitation and understanding of synanthropic species.

La restauración ecológica ayuda en la recuperación de un ecosistema que ha sido degradado. Este proceso en campus universitarios se considera como solución para revertir los procesos de degradación de los ecosistemas. El objetivo es identificar el grado de restauración ecológica en un campus universitario en Oaxaca, mediante el análisis del cambio de uso de suelo ocurrido desde su fundación. Se evaluaron los procesos de restauración en la Universidad de la Sierra Juárez (UNSIJ) mediante imágenes satelitales de 2003 y 2020. Se realizó una clasificación supervisada y el índice de vegetación normalizado. Se analizaron registros históricos de una familia botánica considerada como buen subrogado de la biodiversidad. Se identificaron 81150 sitios de restauración en México, de ellos Oaxaca tiene 4513 y 341 corresponden a la Sierra Norte; uno de ellos en Ixtlán de Juárez corresponde a la UNSIJ. Se documentan en Ixtlán 334 especies de Asteraceae. Las imágenes revelan que la vegetación arbórea y la vegetación secundaria mostraron porcentajes de incremento entre 10 y 25.6%. En general, el suelo erosionado presentó una disminución de superficie. La Universidad ha permitido la restauración de sus recursos naturales, que forman parte de un ambiente con una considerable diversidad biológica característica de la Sierra Norte, por lo que puede ser un sitio considerado exitoso dentro de los estudios de restauración en el estado de Oaxaca. La vegetación del campus muestra notable mejoría en su área, aún con el crecimiento en el número de edificios mucha superficie vegetal natural se ha restablecido

Background: Ageratina is an American genus of the tribe Eupatorieae (Asteraceae), comprising about 320 species. In Mexico, some species of this genus are highly valued for their medicinal properties, particularly A. pichinchensis, A. petiolaris, and A. grandifolia. Furthermore, herbal preparations of A. pichinchensis are available for treating several mycoses. Aim and Objective: The present review is aimed to summarize the chemical and pharmacological properties of 37 species of the Ageratina genus up to April, 2022. Methods: Data were recorded using online scientific databases, including Scopus, PubMed, Google Scholar, Taylor and Francis Imprints, National Center for Biotechnology Information, Science Direct, JSTOR, and SciFinder. The information was gathered from research articles, relevant books on herbal medicinal plants and the history of medicinal plants from Mexico, theses, reports, and web pages. Results: The specialized metabolites present in the Ageratina genus belong to different chemical classes, including flavonoids, benzyl benzoates, benzofurans, chromenes, and terpenoids. The chromenes, benzofurans, and benzyl benzoates are the metabolites most widespread in the genus. So far, the species more thoroughly investigated is A. adenophora. Ageratina has received little attention from the pharmacological point of view. The studies are limited to 10 species. Biological studies have been conducted on extracts and/or compounds isolated from plants collected mainly from China and Mexico. The results revealed that the extracts and metabolites possess several biological activities, including antiviral, antioxidant, antimicrobial, anti-inflammatory, antinociceptive, antifeedant, larvicidal, acaricidal, antidiabetic, antiprotozoal, and wound-healing properties. In the case of A. pichinchensis, A. petiolaris, and A. grandifolia, the pharmacological studies provided evidence for their use for treating gastrointestinal complaints and diabetes. Furthermore, herbal preparations of A. pichinchensis are now widely used for alleviating onychomycosis. A. adenophora, is the most investigated species, chemically and biologically; however, some hepatotoxicity effect has been recorded. Conclusion: This review recapitulates information on the Ageratina genus, highlighting the phytochemistry and biological activities of the species investigated. It is important to point out that the pharmacological potential of this large genus remains largely unexplored.

Nowadays the implementation of artificial neural networks in high-energy physics has obtained excellent results on improving signal detection. In this work we propose to use neural networks (NNs) for event discrimination in HAWC. This observatory is a water Cherenkov gamma-ray detector that in recent years has implemented algorithms to identify horizontal muon tracks. However, these algorithms are not very efficient. In this work we describe the implementation of three NNs: two based on image classification and one based on object detection. Using these algorithms we obtain an increase in the number of identified tracks. The results of this study could be used in the future to improve the performance of the Earth-skimming technique for the indirect measurement of neutrinos with HAWC., Comment: 8 pages, 6 figures, Proceedings of the 37th International Cosmic Ray Conference (ICRC 2021)